d. blood moves from the heart into arteries and into smaller vessels and then back into larger vessels as it makes its way back to the heart.
Explanation:
A closed circulatory system is a system in which blood is separated from the interstitial fluid as it circulates in the blood vessels. In a closed circulatory system blood circulates in one direction that is from the heart and then then returns to the heart again after circulating around one of two routes of circulation. A closed circulatory system can be observed in vertebrates, annelids, mollusks.
A pea plant that has round seeds has the genotype Rr. It is crossed with a pea plant that ... Gregor Mendel used pea plants that were heterozygous for each of two traits- seed colour and seep shape- to generate a dihybrid cross. The phenotypic ratio of the resulting offspring was nine with round and yellow seeds,